Computing networks can include multiple devices including network devices such as routers, switches, and hubs, computing devices such as servers, desktop PCs, laptops, workstations, and peripheral devices, e.g., printers, facsimile devices, and scanners, networked together across a local area network (LAN), a wireless local area network (WLAN), and/or wide area network (WAN).
Multicasting can be used in a network when the same information is needed by a number of devices at the same time. Multicasting can reduce the amount of network resources used when sending the multicasting information to a number of devices by sending the information one time to all of the devices that need the information. Multicasting can include logically routing the multicast information through a network to avoid redundancy and efficiently route the information through the network. In a multicast network, multicast packets can be transferred from special multicast data sourcing routers, such as rendezvous point routers (RPRs) or designated routers (DRs), through other multicast routers on a path in a network. The availability of the multicast routers on a path in a network can determine whether a path can be used to transfer multicast packets between the special multicast data sourcing routers across other routers on a path through the network.